I discovered something that was not in my scan

[FloridaMan]

I departed Atlanta this morning on an IFR plan in extreme clear VMC. I was assigned 5000ft and vectors. At 4000, I noticed that I was not climbing at Vy. I immediately look at my oil/CHT instruments, prop RPM and EGT -- all normal. I was thinking maybe something weird happened and my valves weren't opening all the way or something. 

 

Just as I keyed the mic to ask to return to base, but before I spoke, my hand, nearly subconsciously, advanced the throttle. It had worked its way back because I'd loosened the friction prior to takeoff -- something that I never do. I never bothered to look at my manifold pressure during the diagnostic process. In trainers, I never had the issue as my hand stayed on the throttle, but with the Johnson bar gear, cowl flaps, ram air and flaps, ATC assignments and turning frequencies and the HSI needle and bug, my hand never made it back to the throttle until I needed somewhere to rest it when my left hand took the yoke to key the mic. In my climb, I bet I checked that the gear handle was fully seated in the latch in the floor a half dozen times, and I screwed around with the GNS530 looking at airspace altitudes, checking nearest airports, et cetera. 

 

I found it interesting how my mind worked to diagnose the issue and how I neglected verifying MP in the diagnostic process of a loss in engine power. Had I looked at that in my initial scan, or kept it in my scan, I would have discovered it much earlier, but my workload was such that I somehow subconsciously eliminated monitoring the mp and throttle position. I went to oil pressure and temperature first, then EGT to see if I had a dead magneto, but neglected the very thing that had never changed on me in the past. I just wonder how I might have handled the situation had I been in actual IMC, given the only significant workload that I had this morning was Atlanta's airspace and being distracted by looking outside of the airplane. I see how it might happen where you see it in accident reports when a pilot makes a power off landing with the fuel selector on the empty tank when the other one is full. 

 

I'll add to say that MP is in my scan during cruise and descent to determine how I lean my mixture, estimate fuel burn and set my power in the descent. 

[201er]

Interesting post. MP is definitely TRICKY! Cause it's not an absolute figure. It's coming down as you're climbing so unless it's like below 20" and below 10'000ft, you wouldn't immediately link it to the throttle. RPM is far more obvious. I've had similar bad climb situations where I didn't connect the fact that the gear was still down. Both times it happened was when the emergency gear extension mechanism came unlatched pretakeoff (this is a terrible thing cause it's not something that usually happens in preflight but rather during boarding so really the best practice is for this to be a pretakeoff check item!!!!) and the gear remained down despite hitting the handle up. I usually don't bother looking for the transition light and gear light to go out. I'd much rather focus on the departure, traffic, obstacles, and emergency options (no time to diagnose/fix the problem at that moment even if I were aware the gear didn't retract). One time this was the result of forgetting to retract the flaps because of an abnormal departure.

 

We are good at handling things using SOP but when something goes different, it is a bit scary how unaware and incapable we become. I guess the main solution to your original issue is to be vigilant about using the friction lock and to diagnose obvious problems before speculating on malfunctions. Since I fly LOP a lot your situation would have probably triggered me to check the mixture first and in the process of checking that I'd probably notice the throttle. So yeah, when power is insufficient, check your powerplant controls before checking the gauges. Then gauges. Then gear and flaps. Let's see what others say.

[gregwatts]

Seems to me that you should have heard your engine........! Scan is good but should  also be listening to your engine........always.

 

 

 

 

Just sayin'

[201er]

Seems to me that you should have heard your engine........! Scan is good but should  also be listening to your engine........always.

Well perhaps he's using a Halo headset and you're only using a Lightspeed? Just sayin

[carusoam]

FF might be helpful as well?

Best regards,

-a-

[Super Dave]

Seems to me that you should have heard your engine........! Scan is good but should also be listening to your engine........always.

Just sayin'

I doubt that many of us would notice a reduction in manifold pressure over a period of several minutes by sound alone. RPM maybe, but not MP.

[FloridaMan]

Not to mention that when you're used to cruising around 9000 ft your mp being reduced at 4000 might not be all that noticeable. The engine simply seemed to be running good but not making a lot of power. I had noise canceling active on my headset. I don't have a graphic engine monitor with FF on my plane. That would have been useful and it's on my list of things to add. In addition to my gear, I also remember checking my flaps multiple times too. 

 

In short, I never even looked at the manifold pressure gauge and couldn't tell you what it was when my hand found the throttle. I run ROP and I don't start leaning until I hit 4000 MSL. The purpose of my post was to share an account of how I failed to diagnose a simple issue when under moderate workload. I've never had a gear-up landing, but I assume that those pilots who have, experienced similar workload or non-standard processes that facilitated it. I've put over 200 hours on my tach since I took delivery of the plane just under a year ago; it really surprised me that I was caught by something like this. 

[bnicolette]

I doubt that many of us would notice a reduction in manifold pressure over a period of several minutes by sound alone. RPM maybe, but not MP.

 

I agree especially during the post take off phase when things are busy including communications.

[PMcClure]

Happened to me a couple of times in my F. Once on a hot day with rising terrain. After that, I added the friction lock to the check list and made a habit to keep my hand on the throttle and my fingers in front of the lock and physically keep it WOT in the climb. 

[Cruiser]

My process was to use my thumb and forefinger the slightly loosen the friction lock for any movement of the power control. On takeoff I would push it full in and twist to tighten. Never had a problem loosing power. 

[1964-M20E]

I cannot recall this happeing to me but I do find myself touching the throttle every now and then to make sure it is WOT while at altitude.

[kmyfm20s]

I consider that a check list item. I have had the throttle back off on me in the past and just as you did I scanned first but then I referred to my check list and caught it. Checklist are great for all phases of flight.

[Hank]

I've had the throttle and prop levers move during cruise. On the quadrant, the friction lock knob is over on the right side, out of view. After it moved and gave me an extra 100 RPMs the one time, I now periodically check the gages after setting power and if anything has moved, I reset it and adjust the friction lock.

[wrench]

I got the hint one time after an ATC interuption got in the way of my 6 point climbout check when the BooH wasn't indicating 20 knots faster than a typical SEL sky knocker.

[Marauder]

Interesting discussion. Like Hank's plane, my quadrant friction lock is on the right side. I normally loosen it a bit to advance the controls for take-off, tighten the knob and keep my hand on them until I am cleaned up in the climb. Then I loosen the knob, adjust power if required and tighten again. Once tightened, I have never had them move. Usually works well unless you get distracted in between. For years using the factory analog gauge, I would look for the relative position of the needle against my expectation of where it should be. You fly a plane long enough, you know where needles should be (and shouldn't be). Recently replacing my manifold gauge with an electronic one, a whole different perspective has emerged -- I'm actually looking at a number. On my flight home last night, I normally reduce power a bit. The usual "around 17 inches" is now 16.9 or 17.1. It's driving me nuts!

[1964-M20E]

Interesting discussion. Like Hank's plane, my quadrant friction lock is on the right side. I normally loosen it a bit to advance the controls for take-off, tighten the knob and keep my hand on them until I am cleaned up in the climb. Then I loosen the knob, adjust power if required and tighten again. Once tightened, I have never had them move. Usually works well unless you get distracted in between. For years using the factory analog gauge, I would look for the relative position of the needle against my expectation of where it should be. You fly a plane long enough, you know where needles should be (and shouldn't be). Recently replacing my manifold gauge with an electronic one, a whole different perspective has emerged -- I'm actually looking at a number. On my flight home last night, I normally reduce power a bit. The usual "around 17 inches" is now 16.9 or 17.1. It's driving me nuts!

I too find myself chasing the numbers with the digital guages. Unitl I finally settle down or get busy with something else.

[Marauder]

Interesting discussion. Like Hank's plane, my quadrant friction lock is on the right side. I normally loosen it a bit to advance the controls for take-off, tighten the knob and keep my hand on them until I am cleaned up in the climb. Then I loosen the knob, adjust power if required and tighten again. Once tightened, I have never had them move. Usually works well unless you get distracted in between. For years using the factory analog gauge, I would look for the relative position of the needle against my expectation of where it should be. You fly a plane long enough, you know where needles should be (and shouldn't be). Recently replacing my manifold gauge with an electronic one, a whole different perspective has emerged -- I'm actually looking at a number. On my flight home last night, I normally reduce power a bit. The usual "around 17 inches" is now 16.9 or 17.1. It's driving me nuts!I too find myself chasing the numbers with the digital guages. Unitl I finally settle down or get busy with something else.

It is has indeed turned into a neurotic OCD behavior for me! I'm hoping the novelty will wear off

[FloridaMan]

That is one reason that I don't want digital gauges. I read somewhere that the guy who developed the old analog EGT gauge intentionally left values off of it as they didn't matter. When I was doing my IFR rating in a DA40, I remember disliking the digital altitude, airspeed ribbons and the jumpy rate of turn indicator. I found that watching your altitude bounce up and down 20 feet was much more fatiguing than the sight picture of a clock-faced analog gauge. Not only would you have the numbers jumping around, but you didn't have an image of where your airspeed or altitude should be like you do on the steam gauges. VFR altitude, big hand down; IFR, big hand up. I think having precise data logged is great, but from a human factors perspective, these gadgets should reduce the workload and aid in decision making, not increase the data that the busy pilot of a single pilot aircraft has to interpret. 

[Hank]

You and me both! Durn digital tapes are too distracting, and then it comes up between numbers and tries to put both of them inside the little highlighted box. Color me "not interested," although the data record would be nice to have for review sometimes, it's just not something I want to look at and deal with every day.

 

Also, I don't often adjust my friction lock, I just keep it tight enough for things to not move on their own, but loose enough that I can make them move. Worked well for over five years . . . Now I just check it periodically and adjust as needed.

[Marauder]

You and me both! Durn digital tapes are too distracting, and then it comes up between numbers and tries to put both of them inside the little highlighted box. Color me "not interested," although the data record would be nice to have for review sometimes, it's just not something I want to look at and deal with every day.

 

Also, I don't often adjust my friction lock, I just keep it tight enough for things to not move on their own, but loose enough that I can make them move. Worked well for over five years . . . Now I just check it periodically and adjust as needed.

 

I think it is a matter of adaptation. When I had the Aspen installed, I had a really hard time not looking at the mechanical ASI on finals. After flying with it a bit, the mechanical ASI has been relegated to the backup position and I like being able to look down and see the actual airspeed number. Has improved my attention to precision since I have a real number to shoot for. Not the half way point on my mechanical gauge.